The following article, BREAKING: 43-Yr-Old Father Of 9, Dollar Store Sec Guard, Shot DEAD While Allegedly Trying To Enforce MI Gov Whitmer’s Face Covering Exec Order, was first published on 100PercentFedUp.com.

Will the mainstream media report about the senseless death of a 43-year-old father of nine, who would have been alive today if it were not for VP wannabe, Gretchen Whitmer's executive order that forced him to respond to a customer not wearing a face mask? 

Continue reading: BREAKING: 43-Yr-Old Father Of 9, Dollar Store Sec Guard, Shot DEAD While Allegedly Trying To Enforce MI Gov Whitmer’s Face Covering Exec Order ...

The following article, 77-Yr-Old MI Barber Defies Gov Whitmer’s Shutdown Order: ”I don’t need another mother” Shop Will Stay Open Until “Jesus walks in or until they arrest me” [VIDEO], was first published on 100PercentFedUp.com.

Emergency orders that “non-essential businesses” remain closed during the Covid-19 crisis have devastated small business owners across America. A wave of business owners across the nation are defying executive orders by their governors and opening their businesses anyhow. Yesterday, we reported about a small business owner in the state of Michigan, where Governor Gretchen Whitmer […]

Continue reading: 77-Yr-Old MI Barber Defies Gov Whitmer’s Shutdown Order: ”I don’t need another mother” Shop Will Stay Open Until “Jesus walks in or until they arrest me” [VIDEO] ...

The following article, BREAKING: MI Lawmakers File Lawsuit Challenging Governor’s “Improper” and “Invalid” Emergency Orders: “We’ve attempted to partner with our governor, but she’s rejected”, was first published on 100PercentFedUp.com.

In addition to crushing Michigan's economy, the governor's reckless, one-size-fits-all executive orders are harming an untold number of Michigan citizens.

Continue reading: BREAKING: MI Lawmakers File Lawsuit Challenging Governor’s “Improper” and “Invalid” Emergency Orders: “We’ve attempted to partner with our governor, but she’s rejected” ...

The following article, NY Shame: Workers Who Tested Positive For COVID-19 Were Allowed To Remain On The Job At Nursing Homes, As Death Toll For Nursing Home Patients Exceeds 3,000, was first published on 100PercentFedUp.com.

The coronavirus crisis at New York’s nursing homes is even worse than previously thought. Monday night, the state Department of Health issued new data, adding more than 1,600 people who were presumed to have died of the virus in nursing homes, but did not have a confirmed diagnosis, to the official toll. As of May […]

Continue reading: NY Shame: Workers Who Tested Positive For COVID-19 Were Allowed To Remain On The Job At Nursing Homes, As Death Toll For Nursing Home Patients Exceeds 3,000 ...

The following article, Breaking: Texas AG Calls for Immediate Release of Salon Owner Jailed for Opening…Texas Lt Gov Offers to Pay Salon Owner’s $7k Fine, was first published on 100PercentFedUp.com.

Salon A La Mode owner Shelley Luther opened her salon in defiance of the lockdown order for salons to stay closed during the coronavirus crisis. She boldly ripped. up the citation she was given by the police and refused to shut her doors. Luther hired a lawyer and went to court where an activist judge […]

Continue reading: Breaking: Texas AG Calls for Immediate Release of Salon Owner Jailed for Opening…Texas Lt Gov Offers to Pay Salon Owner’s $7k Fine ...

The following article, Attorney for Jailed Dallas Salon Owner Shelley Luther Slams Obama Loyalist Judge as a “Tiny Tyrant”, was first published on 100PercentFedUp.com.

Warren Norred, attorney for Shelley Luther, joined Tucker Carlson to discuss the decision by an Obama loyalist Texas judge to jail his client for reopening her salon during the COVID-19 pandemic. Norred said the judge has exposed himself for the “tiny tyrant” that he is. The judge jailed Luther and even fined her $7,000. Texas […]

Continue reading: Attorney for Jailed Dallas Salon Owner Shelley Luther Slams Obama Loyalist Judge as a “Tiny Tyrant” ...

The following article, ‘Schiff in Panic Mode’: Sources Say Russia Probe Transcripts Affirm Officials Found Nothing on Collusion, was first published on 100PercentFedUp.com.

Transcripts of House Intelligence Committee interviews have been cleared for release, and Adam Schiff is reportedly in panic mode. Unfortunately for Schiff, top law enforcement and intel officials said they saw no evidence of collusion between the Trump campaign and Russia in the transcripts. Republicans sought and got approval for the release of the transcripts […]

Continue reading: ‘Schiff in Panic Mode’: Sources Say Russia Probe Transcripts Affirm Officials Found Nothing on Collusion ...

The following article, MSNBC’s Brian Williams Chuckles With Dem Strategist as He Gloats, Mocks Trump About Tragic Downturn in Economy: “They were going to lose before this hit. They’re just going to lose worse now”, was first published on 100PercentFedUp.com.

James Carville spoke out before the coronavirus crisis to say that there is no way  Joe Biden has a chance at beating President Trump in the 2020 election. Well, He’s singing a different tune now at the expense of Americans suffering through this horrible pandemic and economic crisis. James Carvill is a Democratic strategist who […]

Continue reading: MSNBC’s Brian Williams Chuckles With Dem Strategist as He Gloats, Mocks Trump About Tragic Downturn in Economy: “They were going to lose before this hit. They’re just going to lose worse now” ...

The following article, Texas Gov Abbott Frees Salon Owner Shelley Luther: “Criminals shouldn’t be released to prevent COVID-19 just to put business owners in their place”, was first published on 100PercentFedUp.com.

Texas Governor Greg Abbott just changed the coronavirus order to free Salon A La Mode owner Shelley Luther from jail. Abbott tweeted out a comment about the poor treatment of the business owner: Throwing Texans in jail whose biz’s shut down through no fault of their own is wrong. I am eliminating jail for violating […]

Continue reading: Texas Gov Abbott Frees Salon Owner Shelley Luther: “Criminals shouldn’t be released to prevent COVID-19 just to put business owners in their place” ...

The following article, Video Scrubbed of Obama-Biden Ambassador To China Praising Their Response to Coronavirus: “I take my hat off to China”, was first published on 100PercentFedUp.com.

During a recent interview on CNN, Obama-Biden ambassador to China (2014-2017) Max Baucus compared standing up to China on the coronavirus to “Hitler in the ’30s.” Baucus has proven himself to be sympathetic to China in recent interviews, where he puts down America and praises the Chinese. The MSNBC video via The Washington Free Beacon […]

Continue reading: Video Scrubbed of Obama-Biden Ambassador To China Praising Their Response to Coronavirus: “I take my hat off to China” ...

The following article, President Trump’s Navy Valet Tests Positive for Coronavirus, was first published on 100PercentFedUp.com.

One of President Trump’s personal Navy valets has tested positive for coronavirus. The valet, a member of the US Navy who works at the White House, had symptoms of the coronavirus Wednesday morning. He was tested, and his test came back positive for the virus. President Trump was reportedly informed about the situation and fake […]

Continue reading: President Trump’s Navy Valet Tests Positive for Coronavirus ...

The following article, Breaking: Justice Department Dropping Michael Flynn Criminal Case, was first published on 100PercentFedUp.com.

Michael Flynn has finally been exonerated. The Associated Press is reporting exclusively that the Justice Department said it is dropping the criminal case against President Trump’s first national security adviser, Michael Flynn. In court documents being filed Thursday, the Justice Department said it is dropping the case “after a considered review of all the facts […]

Continue reading: Breaking: Justice Department Dropping Michael Flynn Criminal Case ...

The following article, Video: Salon Owner Shelley Luther Released from Jail After Obama-Loyalist Judge Sentenced Her to 7 Days, was first published on 100PercentFedUp.com.

Salon A La Mode owner Shelley Luther was just released from jail today. The Texas Supreme Court and Texas Governor Greg Abbott both called for her release today (see below). When Luther left jail she was greeted by supporters who yelled “Shelley’s Free!” She thanked all of the new friends she’s made during this difficult […]

Continue reading: Video: Salon Owner Shelley Luther Released from Jail After Obama-Loyalist Judge Sentenced Her to 7 Days ...

The following article, BREAKING: Michigan’s Radical Governor Extends Lockdown AGAIN…Only One Day After Church Leaders and MI Lawmakers File Suit Against Her, was first published on 100PercentFedUp.com.

Michigan was the first state to see protests against draconian lockdown measures by an overreaching governor. On April 15, the Michigan Conservative Coalition organized an in-vehicle protest in Lansing, MI that drew an estimated 15,000 vehicles. Since that time, several protests by Michigan workers who are being devastated by the one-size-fits-all shut down of the […]

Continue reading: BREAKING: Michigan’s Radical Governor Extends Lockdown AGAIN…Only One Day After Church Leaders and MI Lawmakers File Suit Against Her ...

The following article, Mother of the Year, Michelle Obama Explains How Having Kids Was A “Concession”… Had To Give Up Her “Aspirations and Dreams” [VIDEO], was first published on 100PercentFedUp.com.

While campaigning for her community organizer turned presidential candidate husband, Barack, Michelle Obama told a crowd of his supporters in Milwaukee, Wisconsin that for the first time in her life, she was proud to be an American. Four years later, Michelle Obama was a keynote speaker at the DNC convention, where she told Democrats how […]

Continue reading: Mother of the Year, Michelle Obama Explains How Having Kids Was A “Concession”… Had To Give Up Her “Aspirations and Dreams” [VIDEO] ...

The following article, BREAKING: New Docs Prove Obama Knew Details Of Flynn Wiretapping…Newly Surfaced Video Shows Obama Explaining How He Stays Out Of FBI Investigations, was first published on 100PercentFedUp.com.

Barack Obama knew. Documents released yesterday that were used to exonerate President Trump’s new NSA General Flynn, prove that President Barack Obama was aware of the details of Michael Flynn’s intercepted phone calls on December 16 with then-Russian Ambassador Sergey Kislyak. On January 5, 2017, then-Deputy Attorney General, Sally Yates attended an Oval Office meeting […]

Continue reading: BREAKING: New Docs Prove Obama Knew Details Of Flynn Wiretapping…Newly Surfaced Video Shows Obama Explaining How He Stays Out Of FBI Investigations ...

The following article, BREAKING: President Trump’s Fiery Interview On Fox & Friends…”These are dirty politicians and dirty cops…They put our nation in danger with other nations, including Russia” [VIDEO], was first published on 100PercentFedUp.com.

This morning during a nearly one hour interview with Fox & Friends, President Trump addressed the decision by the DOJ to drop the case against the innocent General Michael Flynn. Trump ripped into the “dirty politicians and dirty cops” who went after General Michael Flynn. President Trump called the players involved in the horrible plot […]

Continue reading: BREAKING: President Trump’s Fiery Interview On Fox & Friends…”These are dirty politicians and dirty cops…They put our nation in danger with other nations, including Russia” [VIDEO] ...

The following article, Fed Judge Releases 21-Yr-Old Man To “Clean and Sober House” After Appearing In Court For Sexually Assaulting 12-Yr-Old Girl For One Month While Hiding In Her Bedroom, was first published on 100PercentFedUp.com.

The normalizing of pedophilia is not a far-right conspiracy theory...

Continue reading: Fed Judge Releases 21-Yr-Old Man To “Clean and Sober House” After Appearing In Court For Sexually Assaulting 12-Yr-Old Girl For One Month While Hiding In Her Bedroom ...

The following article, Greg Gutfeld Levels Ilhan Omar With Epic Response To Her Claim That “White Privilege” Is Reason Charges Were Dropped Against General Flynn, was first published on 100PercentFedUp.com.

Yesterday, after 3 1/2 years of having his character and integrity called into question, President Trump's first NSA, General Michael Flynn was finally...

Continue reading: Greg Gutfeld Levels Ilhan Omar With Epic Response To Her Claim That “White Privilege” Is Reason Charges Were Dropped Against General Flynn ...

The following article, Busted! Late-Night Hack Comedian, Jimmy Kimmel Is Forced To Apologize For Sharing Highly Edited Video Of VP Pence To Make Him Look Bad, was first published on 100PercentFedUp.com.

Last night, Jimmy Kimmel, host of the low-rated, late-night Jimmy Kimmel Show, shared a deceptively edited video clip of Vice President Pence delivering PPE to a nursing home. Today, liberal activist Matt McDermott tweeted the videotaped segment on VP Pence that was edited to make the vice president look like he was faking a delivery […]

Continue reading: Busted! Late-Night Hack Comedian, Jimmy Kimmel Is Forced To Apologize For Sharing Highly Edited Video Of VP Pence To Make Him Look Bad ...

The following article, Video: Dallas Salon Owner Shelley Luther Gets Surprise Visit from Sen Ted Cruz for a Celebratory Haircut, was first published on 100PercentFedUp.com.

When Dallas, Texas salon owner Shelley Luther opened her salon in defiance of the lockdown order in Texas, she was visited numerous times by the local police and then sentenced to 7 days in jail with a fine of $7,000. After public outrage at her punishment, the Texas Supreme Court stepped in to demand her […]

Continue reading: Video: Dallas Salon Owner Shelley Luther Gets Surprise Visit from Sen Ted Cruz for a Celebratory Haircut ...

The Fiat-Chrysler Windsor Assembly Plant looks to be on track for a May 19 reopening according to union leadership.

After being pulled over for what started as a traffic violation, two Windsor men were arrested and face multiple drug, property, and weapon related charges.

Essex County OPP have released a composite drawing of a suspect reported to be impersonating a police officer in Lakeshore.

Ontario’s provincial parks and conservation areas will reopen this week but campgrounds and beaches will continue to be off-limits for now.

Mother's Day is Sunday, but with COVID-19, it's forcing many to change their plans.

Brandon police officers are searching for a man who was caught on camera attempting to pump gas in his car – without prepaying.

A beverage company in the U.S. is inviting moms to let out a ‘quaranscream’ this Mother’s Day on a designated ‘zero-judgement venting hotline’ for a chance to win its wine spritzers.

Little Richard, the self-proclaimed "architect of rock 'n' roll" whose piercing wail, pounding piano and towering pompadour irrevocably altered popular music while introducing black R&B to white America, has died Saturday. He was 87.

Manitoba’s unemployment rate nearly doubled between March and April, according to the monthly report from Statistics Canada released Friday morning.

The empty space next to Winnipeg City Hall that once housed restaurants could be turned into a place to help exploited women.

Instead of May flowers, Manitobans in the southwest part of the province received a blanketing of snow for Mother's Day weekend.

29 August 2019

Research Event

Event participants

Professor Jagjit S. Chadha, Director, NIESR
Dr Kamala Dawar, Senior Lecturer in Law, University of Sussex; Fellow, UKTPO
Dr Michael Gasiorek, Senior Lecturer in Economics, University of Sussex; Director, Interanalysis; Fellow, UKTPO
Chair: Professor Jim Rollo, Deputy Director, UKTPO; Associate Fellow, Chatham House

10 October 2019

This paper examines the governance problems in the monetary system and global trade and regulation. It then explores whether issues have arisen because the US has given up its dominant role, and if so how these might be rectified.

Research Event

Event participants

Michael Gasiorek, Professor of Economics, University of Sussex; Director, Interanalysis; Fellow, UK Trade Policy Observatory, University of Sussex
Julia Magntorn Garrett, Research Officer, UK Trade Policy Observatory, University of Sussex
Prof Jim Rollo, Deputy Director, UK Trade Policy Observatory, University of Sussex; Associate Fellow, Global Economy and Finance Department, Chatham House
Nicolo Tamberi, Research Officer in the Economics of Brexit, University of Sussex
L. Alan Winters, Professor of Economics, Director, UK Trade Policy Observatory, University of Sussex

11 February 2020

15 March 2020

21 April 2020

Telomeres are specific nucleoprotein structures that are located at the ends of linear eukaryotic chromosomes and play crucial roles in genomic stability. Telomere DNA consists of simple repeats of a short G-rich sequence: TTAGGG in mammals and TTTAGGG in most plants. In recent years, the mammalian telomeric G-rich repeats have been shown to form G-quadruplex (G4) structures, which are crucial for modulating telomere functions. Surprisingly, even though plant telomeres are essential for plant growth, development, and environmental adaptions, only few reports exist on plant telomeric G4 DNA (pTG4). Here, using bulk and single-molecule assays, including CD spectroscopy, and single-molecule FRET approaches, we comprehensively characterized the structure and dynamics of a typical plant telomeric sequence, d[GGG(TTTAGGG)3]. We found that this sequence can fold into mixed G4s in potassium, including parallel and antiparallel structures. We also directly detected intermediate dynamic transitions, including G-hairpin, parallel G-triplex, and antiparallel G-triplex structures. Moreover, we observed that pTG4 is unfolded by the AtRecQ2 helicase but not by AtRecQ3. The results of our work shed light on our understanding about the existence, topological structures, stability, intermediates, unwinding, and functions of pTG4.

The atypical trichromatic cyanobacterial phytochrome NpTP1 from Nostoc punctiforme ATCC 29133 is a linear tetrapyrrole (bilin)-binding photoreceptor protein that possesses tandem-cysteine residues responsible for shifting its light-sensing maximum to the violet spectral region. Using bioinformatics and phylogenetic analyses, here we established that tandem-cysteine cyanobacterial phytochromes (TCCPs) compose a well-supported monophyletic phytochrome lineage distinct from prototypical red/far-red cyanobacterial phytochromes. To investigate the light-sensing diversity of this family, we compared the spectroscopic properties of NpTP1 (here renamed NpTCCP) with those of three phylogenetically diverged TCCPs identified in the draft genomes of Tolypothrix sp. PCC7910, Scytonema sp. PCC10023, and Gloeocapsa sp. PCC7513. Recombinant photosensory core modules of ToTCCP, ScTCCP, and GlTCCP exhibited violet-blue–absorbing dark-states consistent with dual thioether-linked phycocyanobilin (PCB) chromophores. Photoexcitation generated singly-linked photoproduct mixtures with variable ratios of yellow-orange and red-absorbing species. The photoproduct ratio was strongly influenced by pH and by mutagenesis of TCCP- and phytochrome-specific signature residues. Our experiments support the conclusion that both photoproduct species possess protonated 15E bilin chromophores, but differ in the ionization state of the noncanonical “second” cysteine sulfhydryl group. We found that the ionization state of this and other residues influences subsequent conformational change and downstream signal transmission. We also show that tandem-cysteine phytochromes present in eukaryotes possess similar amino acid substitutions within their chromophore-binding pocket, which tune their spectral properties in an analogous fashion. Taken together, our findings provide a roadmap for tailoring the wavelength specificity of plant phytochromes to optimize plant performance in diverse natural and artificial light environments.

Previous studies have shown that sphingosine kinase interacting protein (SKIP) inhibits sphingosine kinase (SK) function in fibroblasts. SK phosphorylates sphingosine producing the potent signaling molecule sphingosine-1-phosphate (S1P). SKIP gene (SPHKAP) expression is silenced by hypermethylation of its promoter in acute myeloid leukemia (AML). However, why SKIP activity is silenced in primary AML cells is unclear. Here, we investigated the consequences of SKIP down-regulation in AML primary cells and the effects of SKIP re-expression in leukemic cell lines. Using targeted ultra-HPLC-tandem MS (UPLC-MS/MS), we measured sphingolipids (including S1P and ceramides) in AML and control cells. Primary AML cells had significantly lower SK activity and intracellular S1P concentrations than control cells, and SKIP-transfected leukemia cell lines exhibited increased SK activity. These findings show that SKIP re-expression enhances SK activity in leukemia cells. Furthermore, other bioactive sphingolipids such as ceramide were also down-regulated in primary AML cells. Of note, SKIP re-expression in leukemia cells increased ceramide levels 2-fold, inactivated the key signaling protein extracellular signal-regulated kinase, and increased apoptosis following serum deprivation or chemotherapy. These results indicate that SKIP down-regulation in AML reduces SK activity and ceramide levels, an effect that ultimately inhibits apoptosis in leukemia cells. The findings of our study contrast with previous results indicating that SKIP inhibits SK function in fibroblasts and therefore challenge the notion that SKIP always inhibits SK activity.

The transcription factor forkhead box P3 (FOXP3) is a biomarker for regulatory T cells and can also be expressed in cancer cells, but its function in cancer appears to be divergent. The role of hepatocyte-expressed FOXP3 in hepatocellular carcinoma (HCC) is unknown. Here, we collected tumor samples and clinical information from 115 HCC patients and used five human cancer cell lines. We examined FOXP3 mRNA sequences for mutations, used a luciferase assay to assess promoter activities of FOXP3's target genes, and employed mouse tumor models to confirm in vitro results. We detected mutations in the FKH domain of FOXP3 mRNAs in 33% of the HCC tumor tissues, but in none of the adjacent nontumor tissues. None of the mutations occurred at high frequency, indicating that they occurred randomly. Notably, the mutations were not detected in the corresponding regions of FOXP3 genomic DNA, and many of them resulted in amino acid substitutions in the FKH region, altering FOXP3's subcellular localization. FOXP3 delocalization from the nucleus to the cytoplasm caused loss of transcriptional regulation of its target genes, inactivated its tumor-inhibitory capability, and changed cellular responses to histone deacetylase (HDAC) inhibitors. More complex FKH mutations appeared to be associated with worse prognosis in HCC patients. We conclude that mutations in the FKH domain of FOXP3 mRNA frequently occur in HCC and that these mutations are caused by errors in transcription and are not derived from genomic DNA mutations. Our results suggest that transcriptional mutagenesis of FOXP3 plays a role in HCC.

Prostate cancer (PCa) cells heavily rely on an active androgen receptor (AR) pathway for their survival. Enzalutamide (MDV3100) is a second-generation antiandrogenic drug that was approved by the Food and Drug Administration in 2012 to treat patients with castration-resistant prostate cancer (CRPC). However, emergence of resistance against this drug is inevitable, and it has been a major challenge to develop interventions that help manage enzalutamide-resistant CRPC. Erythropoietin-producing human hepatocellular (Eph) receptors are targeted by ephrin protein ligands and have a broad range of functions. Increasing evidence indicates that this signaling pathway plays an important role in tumorigenesis. Overexpression of EPH receptor B4 (EPHB4) has been observed in multiple types of cancer, being closely associated with proliferation, invasion, and metastasis of tumors. Here, using RNA-Seq analyses of clinical and preclinical samples, along with several biochemical and molecular methods, we report that enzalutamide-resistant PCa requires an active EPHB4 pathway that supports drug resistance of this tumor type. Using a small kinase inhibitor and RNAi-based gene silencing to disrupt EPHB4 activity, we found that these disruptions re-sensitize enzalutamide-resistant PCa to the drug both in vitro and in vivo. Mechanistically, we found that EPHB4 stimulates the AR by inducing proto-oncogene c-Myc (c-Myc) expression. Taken together, these results provide critical insight into the mechanism of enzalutamide resistance in PCa, potentially offering a therapeutic avenue for enhancing the efficacy of enzalutamide to better manage this common malignancy.

The peroxisome is a subcellular organelle that functions in essential metabolic pathways, including biosynthesis of plasmalogens, fatty acid β-oxidation of very-long-chain fatty acids, and degradation of hydrogen peroxide. Peroxisome biogenesis disorders (PBDs) manifest as severe dysfunction in multiple organs, including the central nervous system (CNS), but the pathogenic mechanisms in PBDs are largely unknown. Because CNS integrity is coordinately established and maintained by neural cell interactions, we here investigated whether cell-cell communication is impaired and responsible for the neurological defects associated with PBDs. Results from a noncontact co-culture system consisting of primary hippocampal neurons with glial cells revealed that a peroxisome-deficient astrocytic cell line secretes increased levels of brain-derived neurotrophic factor (BDNF), resulting in axonal branching of the neurons. Of note, the BDNF expression in astrocytes was not affected by defects in plasmalogen biosynthesis and peroxisomal fatty acid β-oxidation in the astrocytes. Instead, we found that cytosolic reductive states caused by a mislocalized catalase in the peroxisome-deficient cells induce the elevation in BDNF secretion. Our results suggest that peroxisome deficiency dysregulates neuronal axogenesis by causing a cytosolic reductive state in astrocytes. We conclude that astrocytic peroxisomes regulate BDNF expression and thereby support neuronal integrity and function.

The Mycobacterium tuberculosis virulence factor EsxA and its chaperone EsxB are secreted as a heterodimer (EsxA:B) and are crucial for mycobacterial escape from phagosomes and cytosolic translocation. Current findings support the idea that for EsxA to interact with host membranes, EsxA must dissociate from EsxB at low pH. However, the molecular mechanism by which the EsxA:B heterodimer separates is not clear. In the present study, using liposome-leakage and cytotoxicity assays, LC-MS/MS–based proteomics, and CCF-4 FRET analysis, we obtained evidence that the Nα-acetylation of the Thr-2 residue on EsxA, a post-translational modification that is present in mycobacteria but absent in Escherichia coli, is required for the EsxA:B separation. Substitutions at Thr-2 that precluded Nα-acetylation inhibited the heterodimer separation and hence prevented EsxA from interacting with the host membrane, resulting in attenuated mycobacterial cytosolic translocation and virulence. Molecular dynamics simulations revealed that at low pH, the Nα-acetylated Thr-2 makes direct and frequent “bind-and-release” contacts with EsxB, which generates a force that pulls EsxB away from EsxA. In summary, our findings provide evidence that the Nα-acetylation at Thr-2 of EsxA facilitates dissociation of the EsxA:B heterodimer required for EsxA membrane permeabilization and mycobacterial cytosolic translocation and virulence.

Type 2 diabetes mellitus (T2DM) is characterized by impaired glucose-stimulated insulin secretion and increased peripheral insulin resistance. Unremitting endoplasmic reticulum (ER) stress can lead to beta-cell apoptosis and has been linked to type 2 diabetes. Although many studies have attempted to link ER stress and T2DM, the specific effects of ER stress on beta-cell function remain incompletely understood. To determine the interrelationship between ER stress and beta-cell function, here we treated insulin-secreting INS-1(832/13) cells or isolated mouse islets with the ER stress–inducer tunicamycin (TM). TM induced ER stress as expected, as evidenced by activation of the unfolded protein response. Beta cells treated with TM also exhibited concomitant alterations in their electrical activity and cytosolic free Ca2+ oscillations. As ER stress is known to reduce ER Ca2+ levels, we tested the hypothesis that the observed increase in Ca2+ oscillations occurred because of reduced ER Ca2+ levels and, in turn, increased store-operated Ca2+ entry. TM-induced cytosolic Ca2+ and membrane electrical oscillations were acutely inhibited by YM58483, which blocks store-operated Ca2+ channels. Significantly, TM-treated cells secreted increased insulin under conditions normally associated with only minimal release, e.g. 5 mm glucose, and YM58483 blocked this secretion. Taken together, these results support a critical role for ER Ca2+ depletion–activated Ca2+ current in mediating Ca2+-induced insulin secretion in response to ER stress.

The protein-tyrosine phosphatase SHP2 is an allosteric enzyme critical for cellular events downstream of growth factor receptors. Mutations in the SHP2 gene have been linked to many different types of human diseases, including developmental disorders, leukemia, and solid tumors. Unlike most SHP2-activating mutations, the T507K substitution in SHP2 is unique in that it exhibits oncogenic Ras-like transforming activity. However, the biochemical basis of how the SHP2/T507K variant elicits transformation remains unclear. By combining kinetic and biophysical methods, X-ray crystallography, and molecular modeling, as well as using cell biology approaches, here we uncovered that the T507K substitution alters both SHP2 substrate specificity and its allosteric regulatory mechanism. We found that although SHP2/T507K exists in the closed, autoinhibited conformation similar to the WT enzyme, the interactions between its N-SH2 and protein-tyrosine phosphatase domains are weakened such that SHP2/T507K possesses a higher affinity for the scaffolding protein Grb2-associated binding protein 1 (Gab1). We also discovered that the T507K substitution alters the structure of the SHP2 active site, resulting in a change in SHP2 substrate preference for Sprouty1, a known negative regulator of Ras signaling and a potential tumor suppressor. Our results suggest that SHP2/T507K's shift in substrate specificity coupled with its preferential association of SHP2/T507K with Gab1 enable the mutant SHP2 to more efficiently dephosphorylate Sprouty1 at pTyr-53. This dephosphorylation hyperactivates Ras signaling, which is likely responsible for SHP2/T507K's Ras-like transforming activity.